He toured Australia for the first time in March last year, playing the CMC Rocks festival in Queensland.
Aldean wrote on Instagram "Tonight has been beyond horrific. I still don't know what to say but wanted to let everyone know that me and my crew are safe. My thoughts and prayers go out to everyone involved tonight. It hurts my heart that this would happen to anyone who was just coming out to enjoy what should have been a fun night."
He added the hashtags #heartbroken and #stopthehate.
Aldean has two children and his wife is pregnant with their third.
Russell Brand lashes out
The comments come after Russell Brand blasted American gun laws and "normalised" mass shootings after the Las Vegas shooting tragedy.
"It's interesting that America's ideas about freedom to purchase arms continues to hold the imagination so strongly even after Sandy Hook," Brand said, in a video he posted online from the United States.
"It's sort of tragic that as I'm looking at this, I'm not thinking, 'What?! Fifty people have died?!' Instead, it's like 'one of those things has happened'. It is already normalised by virtue of the fact it happens a lot."
The British comedian, who cancelled a scheduled TV appearance to promote his new book on the US Today show after the tragedy, also debated what drove the violence.
"What is it that's bubbling up from under the surface in the form of violence of this kind?" Brand said in the video.
"I would argue that it's extreme unhappiness, extreme darkness, an unaddressed darkness.
"This social phenomena occurring this regularly and our ability to see it as kind of normal is an indication that we need to address the root cause, and the root cause is always the consciousness of human beings on an individual and social level.
"This won't stop happening unless we change our mentality."
Mariah Carey also gave a shock interview in which she was blindsided by the news and struggled to react appropriately when put on the spot.
She later tweeted her prayers along with a host of other stars who took the opportunity to demand stricter gun control laws in the US.